This invention relates to mobile communications, and specifically to the elimination of speech drop-outs for certain voice transmissions.
Effective voice recognition technology can reduce the need for keypads and large displays. This is important when considering portable devices which are intended to connect to the world-wide communications network known as the internet. The problem is that current voice recognition technology, which is suitable for use on portable, battery-powered devices, fails to achieve needed speed or accuracy. The solution, because such products are intended to connect wirelessly to a network, is to install voice recognition hardware and software on network-based servers which a user can dial into.
Server-based recognition systems are in widespread use in wired telephone networks for such tasks as directory assistance and simple data look-up, and work well as long as the caller is using a wired telephone. Problems develop, however, when a digital wireless, e.g., cellular or PCS, telephone is used. This is because speech processing algorithms in use by all major wireless standards, such as GSM, IS-136, IS-95 and PDC, do not provide for error-free transmission. This results in signal corruption, which appear as muted xe2x80x9cblocksxe2x80x9d of speech, on the order of 20 ms each. To improve the perceived voice quality at the receiving end, these same systems often perform some form of extrapolation or smoothing operation to make the corruption less noticeable to the human auditory system. Unfortunately, tests have established that the underlying corruption and the follow-on extrapolation or smoothing renders the received speech nearly imperceptible to high-performance server-based speech recognition systems. Prior art systems and methods do not offer a meaningful solution to the aforementioned problem, however, a number of attempts have been made to provide speech recognition systems and GSM communications, although very little work has been done to combine the two fields of art.
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A speech encoding system for use with a digital cellular communication device and a receiving station, includes a mechanism for determining whether a voice communications packet needs to be treated as a data communications packet; a voice recognition mechanism for receiving instructions by voice command; and a control mechanism for responding to said voice command and controlling a controlled entity.
A method for encoding a voice command generated on a digital cellular communication device and transmitted over a wireless communication network to a receiving station for controlling a controllable entity includes recognizing a voice command; determining whether the voice command needs to be treated as a data communications packet; encoding the voice command; connecting the voice command to a voice recognition mechanism; and controlling a controlled entity with the voice command.
An object of the invention is to provide error-free voice transmission for providing voice control of a controlled entity.
Another object of the invention is to provide a voice recognition system for use with a digital cellular phone system.